Localization for mobile devices

ABSTRACT

Systems and methods for localization for mobile devices are described. Some implementations may include accessing motion data captured using one or more motion sensors; determining, based on the motion data, a coarse localization, wherein the coarse localization includes a first estimate of position; obtaining one or more feature point maps, wherein the feature point maps are associated with a position of the coarse localization; accessing images captured using one or more image sensors; determining, based on the images, a fine localization pose by localizing into a feature point map of the one or more feature point maps, wherein the fine localization pose includes a second estimate of position and an estimate of orientation; generating, based on the fine localization pose, a virtual object image including a view of a virtual object; and displaying the virtual object image.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/575,712, filed on Sep. 19, 2019, which claims the benefit of U.S.Provisional Application No. 62/736,516, filed on Sep. 26, 2018, entitled“Localization for Mobile Devices,” the content of which are incorporatedherein by reference in their entirety for all purposes.

TECHNICAL FIELD

This disclosure relates to localization for mobile devices.

BACKGROUND

Head-mounted displays are used to provide computer-generated reality(CGR) experiences for users. Objects of a virtual environment may berendered at positions in a coordinate system of a head-mounted display.

SUMMARY

Disclosed herein are implementations of localization for mobile devices.

In a first aspect, the subject matter described in this specificationcan be embodied in systems that include a head-mounted display, one ormore image sensors coupled to the head-mounted display, and one or moremotion sensors coupled to the head-mounted display. The systems includea processing apparatus configured to access motion data captured usingthe one or more motion sensors; determine, based on the motion data, acoarse localization pose, wherein the coarse localization pose includesa first estimate of position of the head-mounted display and a firstestimate of orientation of the head-mounted display; obtain one or morefeature point maps, wherein the feature point maps are associated with aposition of the coarse localization pose; access images captured usingthe one or more image sensors; determine, based on the images, a finelocalization pose by localizing into a feature point map of the one ormore feature point maps, wherein the fine localization pose includes asecond estimate of position of the head-mounted display and a secondestimate of orientation of the head-mounted display; generate, based onthe fine localization pose, a virtual object image including a view of avirtual object; and display the virtual object image using thehead-mounted display.

In a second aspect, the subject matter described in this specificationcan be embodied in methods that include, at an electronic device havingone or more motion sensors, accessing motion data captured using the oneor more motion sensors; determining, based on the motion data, a coarselocalization, wherein the coarse localization includes a first estimateof position of the electronic device; obtaining one or more featurepoint maps, wherein the feature point maps are associated with aposition of the coarse localization; accessing images captured using oneor more image sensors; determining, based on the images, a finelocalization pose by localizing into a feature point map of the one ormore feature point maps, wherein the fine localization pose includes asecond estimate of position and an estimate of orientation; generating,based on the fine localization pose, a virtual object image including aview of a virtual object; and displaying the virtual object image.

In a third aspect, the subject matter described in this specificationcan be embodied in systems that include a server configured to accessfeature point maps stored in a spatially partitioned data structure, andselect one or more feature point maps from the spatially partitioneddata structure based on an estimate of position; and a mobile computingdevice configured to determine a coarse localization including anestimate of position based on motion sensor data, transmit a request tothe server that includes the coarse localization, and receive one ormore feature point maps from the server that are selected by the serverbased on the coarse localization, determine a fine localization pose bylocalizing into a feature point map of the one or more feature pointmaps using captured images, wherein the fine localization pose includesa second estimate of position and an estimate of orientation, generate avirtual object image including a view of a virtual object based on thefine localization pose, and display the virtual object image.

In a fourth aspect, the subject matter described in this specificationcan be embodied in a non-transitory computer-readable storage medium.The non-transitory computer-readable storage medium may includeexecutable instructions that, when executed by a processor, facilitateperformance of operations, including accessing motion data capturedusing one or more motion sensors; determining, based on the motion data,a coarse localization, wherein the coarse localization includes a firstestimate of position; obtaining one or more feature point maps, whereinthe feature point maps are associated with a position of the coarselocalization; accessing images captured using one or more image sensors;determining, based on the images, a fine localization pose by localizinginto a feature point map of the one or more feature point maps, whereinthe fine localization pose includes a second estimate of position and anestimate of orientation; generating, based on the fine localizationpose, a virtual object image including a view of a virtual object; anddisplaying the virtual object image.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure is best understood from the following detaileddescription when read in conjunction with the accompanying drawings. Itis emphasized that, according to common practice, the various featuresof the drawings are not to-scale. On the contrary, the dimensions of thevarious features are arbitrarily expanded or reduced for clarity.

FIG. 1 is a block diagram of an example of a system configured to enablelocalization for CGR applications.

FIG. 2 is a block diagram of an example of a system configured to enablelocalization for CGR applications.

FIG. 3 is a block diagram of an example of a mobile computing device 300configured to enable localization for CGR applications.

FIG. 4 is a block diagram of an example of a system configured to enablelocalization for CGR applications.

FIG. 5 is a block diagram of an example of a localization serverconfigured to enable localization for CGR applications.

FIG. 6 is a flowchart of an example of a process for localization forCGR applications.

FIG. 7 is a flowchart of an example of a process for obtaining featurepoint maps associated with a coarse localization.

FIG. 8 is a flowchart of an example of a process for iterativelyobtaining feature point maps associated with a coarse localization todetermine a fine localization.

FIG. 9 is a flowchart of an example of a process for identifying one ormore feature point maps for transmission based on a coarse localization.

DETAILED DESCRIPTION

Described herein are systems and methods that provide a way for a mobiledevice to, with a high degree of accuracy and stability, determine itslocation and orientation in a coordinate system (e.g., a globalcoordinate system relative to the Earth). For example, these systems andmethods may be used in the context of CGR applications with real worldsemantics, in which GPS alone may be insufficient because of accuracyand noise issues.

A global coordinate system is a system in which points on and above thesurface of the Earth are associated with a unique coordinate tuplerelative to the center of the Earth (e.g., a Cartesian coordinate(x,y,z) or a spherical coordinate (θ,φ,r) or (lat, long, altitude)). Aglobal position is a translation delta from the origin of the globalcoordinate system. A global orientation is a rotation delta from theidentify transformation in the global coordinate system. For example, anorientation may be encoded as a quaternion or a 3×3 rotation matrix. Apose includes a position and an orientation in a coordinate system. Apose may have six degrees of freedom. A global pose is a combined globalposition and global orientation. For example, a pose may be encoded as a4×4 matrix or as a combination of three floating point values (e.g., theglobal position) and either a quaternion or a 3×3 matrix (e.g., theglobal orientation).

Coarse localization is a process of determining the device's coordinate(e.g., a global coordinate) quickly, but with degrees of uncertainty,noise and/or instability. For example, coarse localization may beperformed by processing measurements or sensor readings from one or moreof the following types of motion sensors: GPS receivers, Wi-Fi orcellular triangulation, compasses, barometers, and/or inertialmeasurement units. A coarse localization can also refer to a result of acoarse localization process, which may include a position and/or anorientation (e.g., a coarse localization pose that includes both aposition and an orientation).

Fine localization is a method of determining a device's coordinate(e.g., a global coordinate) with a higher degree of accuracy andstability than a coarse localization. Fine localization may compareimages of a space captured from a device of interest to a model of thephysical objects known to exist in the region of space to find a matchto the perspective from device of interest that may indicate a pose ofthe device of interest when the images were captured. For example,bundle adjustment processing (e.g., using a SLAM (SimultaneousLocalization And Mapping) algorithm) may be applied to localize into afeature point map to determine a pose of the device with high accuracyand stability. For example, in some CGR applications that rendergraphical representations of virtual objects (e.g., as 3D graphics) inreal-world locations, the accuracy of a fine localization may typicallybe on the order of global position errors less than 10 cm and globalorientation errors less than 0.1 degrees. A fine localization can alsorefer to a result of a fine localization process, which may include aposition and/or an orientation (e.g., a fine localization pose thatincludes both a position and an orientation).

A feature point map is a collection of feature points (e.g., stored as alist of feature points) that can be used by computer vision algorithms.A feature point has a position (e.g., a position in a global coordinatesystem). For example, a feature point may include a three-tuple offloats that specify its position. In some implementations, a featurepoint may include one or more additional channels of data that describeproperties of a feature point (e.g., colors or local textures). Afeature point map may be associated with a region of space and mayinclude feature points occurring within that region of space (e.g., acube, a sphere, or a room). Feature point scanning is a process (e.g., amanual process) for collection of feature points and generating afeature point map of a location in the real world. For example, featurepoint scanning may be carried out using the same type of device thatwill later use the feature point map for CGR applications. For example,feature point scanning may be carried out using specialized scanninghardware including an array of image sensors and high precision sensorsfor surveying to determine a track an evolving pose of the array ofimage sensors.

Localization is a process by which a CGR application attempts to finelocalize itself given an existing feature point map. For example, bundleadjustment processing (e.g., using a SLAM (Simultaneous Localization AndMapping) algorithm) may be applied to localize into a feature point mapto determine a fine localization pose. For example, a localizationprocess may fail in scenarios where the device is not actually in theregion of space where those feature points exist, or if that region haschanged, or if that region was not sufficiently scanned. A mobilecomputing device is a computing device which is typically moved orcarried in everyday life. Some examples of mobile computing devicesinclude a smartphone, a smartwatch, a tablet, or a head-mounted display(e.g., smart glasses). To facilitate operation of a CGR application, amobile computing device may have access to two capabilities: alocalization service, which may include a service or server or cloudasset that is running and accessible via the internet to assist a mobilecomputing device with coarse localization and/or fine localization; anda content service, which may include a service or server or cloud assetthat is running and accessible via the interne that vends content to theapplication based on a global pose. Some implementations use a world mapdatabase, which is a database that exists as part of the localizationservice containing a spatially partitioned cache of feature point maps.

For example, operations of a system may include 1) an application startsup on a mobile computing device (e.g., a head-mounted display) andqueries its coarse localization global pose. 2) A connection may beestablished with the localization service. 3) A coarse localization poseof the mobile computing device may be transmitted to the localizationservice. 4) The localization service may search a world map database forrelevant, potential feature point maps using application specific searchheuristics. 5) The localization service may begin streaming potentialfeature point maps back to the mobile computing device. 6) The mobilecomputing device attempts to localize into the feature point maps thatthe localization service is streaming to it. In the case of success atstep 6), the mobile computing device is now fine localized. The mobilecomputing device may then contact the content service with the finelocalization global pose to start streaming content associated with thereal world location where the device is positioned to enablepresentation of the content to a user. In the case of failure at step6), localization was not possible into any of the candidate featurepoint maps. The mobile computing device may at this point tell thelocalization service to try a different search heuristic or broaden thesearch to additional feature point maps, eventually giving up anddisplaying some sort of “Failed to localize” message if localization isnot successful.

Some implementations may provide advantages over earlier systems forlocalization for CGR applications, such as, reducing delay and/orprocessing resources (e.g., processor cycles, memory, and/or power) forperforming a fine localization to a global coordinate system. Someimplementations may enable the use of a centralized collection offeature point maps that can be frequently updated at scale to accountfor frequent changes in the layout of spaces.

Physical Environment

-   -   a. A physical environment refers to a physical world that people        can sense and/or interact with without aid of electronic        systems. Physical environments, such as a physical park, include        physical articles, such as physical trees, physical buildings,        and physical people. People can directly sense and/or interact        with the physical environment, such as through sight, touch,        hearing, taste, and smell.

Computer-generated reality

-   -   a. In contrast, a computer-generated reality (CGR) environment        refers to a wholly or partially simulated environment that        people sense and/or interact with via an electronic system. In        CGR, a subset of a person's physical motions, or representations        thereof, are tracked, and, in response, one or more        characteristics of one or more virtual objects simulated in the        CGR environment are adjusted in a manner that comports with at        least one law of physics. For example, a CGR system may detect a        person's head turning and, in response, adjust graphical content        and an acoustic field presented to the person in a manner        similar to how such views and sounds would change in a physical        environment. In some situations (e.g., for accessibility        reasons), adjustments to characteristic(s) of virtual object(s)        in a CGR environment may be made in response to representations        of physical motions (e.g., vocal commands).    -   b. A person may sense and/or interact with a CGR object using        any one of their senses, including sight, sound, touch, taste,        and smell. For example, a person may sense and/or interact with        audio objects that create 3D or spatial audio environment that        provides the perception of point audio sources in 3D space. In        another example, audio objects may enable audio transparency,        which selectively incorporates ambient sounds from the physical        environment with or without computer-generated audio. In some        CGR environments, a person may sense and/or interact only with        audio objects.    -   c. Examples of CGR include virtual reality and mixed reality.

Virtual reality

-   -   a. A virtual reality (VR) environment refers to a simulated        environment that is designed to be based entirely on        computer-generated sensory inputs for one or more senses. A VR        environment comprises a plurality of virtual objects with which        a person may sense and/or interact. For example,        computer-generated imagery of trees, buildings, and avatars        representing people are examples of virtual objects. A person        may sense and/or interact with virtual objects in the VR        environment through a simulation of the person's presence within        the computer-generated environment, and/or through a simulation        of a subset of the person's physical movements within the        computer-generated environment.

Mixed reality

-   -   a. In contrast to a VR environment, which is designed to be        based entirely on computer-generated sensory inputs, a mixed        reality (MR) environment refers to a simulated environment that        is designed to incorporate sensory inputs from the physical        environment, or a representation thereof, in addition to        including computer-generated sensory inputs (e.g., virtual        objects). On a virtuality continuum, a mixed reality environment        is anywhere between, but not including, a wholly physical        environment at one end and virtual reality environment at the        other end.    -   b. In some MR environments, computer-generated sensory inputs        may respond to changes in sensory inputs from the physical        environment. Also, some electronic systems for presenting an MR        environment may track location and/or orientation with respect        to the physical environment to enable virtual objects to        interact with real objects (that is, physical articles from the        physical environment or representations thereof). For example, a        system may account for movements so that a virtual tree appears        stationery with respect to the physical ground.    -   c. Examples of mixed realities include augmented reality and        augmented virtuality.    -   d. Augmented reality        -   i. An augmented reality (AR) environment refers to a            simulated environment in which one or more virtual objects            are superimposed over a physical environment, or a            representation thereof. For example, an electronic system            for presenting an AR environment may have a transparent or            translucent display through which a person may directly view            the physical environment. The system may be configured to            present virtual objects on the transparent or translucent            display, so that a person, using the system, perceives the            virtual objects superimposed over the physical environment.            Alternatively, a system may have an opaque display and one            or more imaging sensors that capture images or video of the            physical environment, which are representations of the            physical environment. The system composites the images or            video with virtual objects, and presents the composition on            the opaque display. A person, using the system, indirectly            views the physical environment by way of the images or video            of the physical environment, and perceives the virtual            objects superimposed over the physical environment. As used            herein, a video of the physical environment shown on an            opaque display is called “pass-through video,” meaning a            system uses one or more image sensor(s) to capture images of            the physical environment, and uses those images in            presenting the AR environment on the opaque display. Further            alternatively, a system may have a projection system that            projects virtual objects into the physical environment, for            example, as a hologram or on a physical surface, so that a            person, using the system, perceives the virtual objects            superimposed over the physical environment.        -   ii. An augmented reality environment also refers to a            simulated environment in which a representation of a            physical environment is transformed by computer-generated            sensory information. For example, in providing pass-through            video, a system may transform one or more sensor images to            impose a select perspective (e.g., viewpoint) different than            the perspective captured by the imaging sensors. As another            example, a representation of a physical environment may be            transformed by graphically modifying (e.g., enlarging)            portions thereof, such that the modified portion may be            representative but not photorealistic versions of the            originally captured images. As a further example, a            representation of a physical environment may be transformed            by graphically eliminating or obfuscating portions thereof.    -   e. Augmented virtuality        -   i. An augmented virtuality (AV) environment refers to a            simulated environment in which a virtual or computer            generated environment incorporates one or more sensory            inputs from the physical environment. The sensory inputs may            be representations of one or more characteristics of the            physical environment. For example, an AV park may have            virtual trees and virtual buildings, but people with faces            photorealistically reproduced from images taken of physical            people. As another example, a virtual object may adopt a            shape or color of a physical article imaged by one or more            imaging sensors. As a further example, a virtual object may            adopt shadows consistent with the position of the sun in the            physical environment.

Hardware

-   -   a. There are many different types of electronic systems that        enable a person to sense and/or interact with various CGR        environments. Examples include head mounted systems,        projection-based systems, heads-up displays (HUDs), vehicle        windshields having integrated display capability, windows having        integrated display capability, displays formed as lenses        designed to be placed on a person's eyes (e.g., similar to        contact lenses), headphones/earphones, speaker arrays, input        systems (e.g., wearable or handheld controllers with or without        haptic feedback), smartphones, tablets, and desktop/laptop        computers. A head mounted system may have one or more speaker(s)        and an integrated opaque display. Alternatively, a head mounted        system may be configured to accept an external opaque display        (e.g., a smartphone). The head mounted system may incorporate        one or more imaging sensors to capture images or video of the        physical environment, and/or one or more microphones to capture        audio of the physical environment. Rather than an opaque        display, a head mounted system may have a transparent or        translucent display. The transparent or translucent display may        have a medium through which light representative of images is        directed to a person's eyes. The display may utilize digital        light projection, OLEDs, LEDs, uLEDs, liquid crystal on silicon,        laser scanning light source, or any combination of these        technologies. The medium may be an optical waveguide, a hologram        medium, an optical combiner, an optical reflector, or any        combination thereof. In one embodiment, the transparent or        translucent display may be configured to become opaque        selectively. Projection-based systems may employ retinal        projection technology that projects graphical images onto a        person's retina. Projection systems also may be configured to        project virtual objects into the physical environment, for        example, as a hologram or on a physical surface.

FIG. 1 is a block diagram of an example of a system 100 configured toenable localization for CGR applications. The system 100 includes amobile computing device 110 that includes one or more image sensors forcapturing images of local surroundings 112. The mobile computing device110 is configured to communicate via a communications network 106 (e.g.,the Internet or another wide area network, or a local area network) witha localization server 120 configured to feature point maps to assistwith fine localization of the mobile computing device 110, and a contentserver 130 configured to provide content associated with the localsurroundings 112 to a CGR application running on the mobile computingdevice 110 based on the fine localization (e.g., including a globalposition and/or a global orientation).

The system 100 includes a localization server 120 configured to accessfeature point maps stored in a spatially partitioned data structure, andselect one or more feature point maps from the spatially partitioneddata structure based on an estimate of position. For example, theestimate of position may be determined as a coarse localization based onmotion sensor data for the mobile computing device 110. For example, thelocalization server 120 may implement the process 900 of FIG. 9. Forexample, the feature point maps stored in a spatially partitioned datastructure may have been generated using a feature extraction processbased on images captured of regions of space from known positions. Forexample, the localization server 120 may be implemented on thelocalization server 500 of FIG. 5. In some implementations, thespatially partitioned data structure is stored by the localizationserver (e.g., in the data storage device 520). In some implementations,the spatially partitioned data structure is stored in a separatedatabase server (not shown) and accessed by the localization server viathe communications network 106.

The system 100 includes a mobile computing device 110 configured todetermine a coarse localization including an estimate of position basedon motion sensor data. For example, the motion sensor data may includemotion sensor data from a global positioning system (GPS) receiverattached to the mobile computing device 110. For example, the motionsensor data may include motion sensor data from an inertial measurementunit attached to the mobile computing device 110. For example, themotion sensor data may include motion sensor data from wireless signalreceivers that are configured to triangulate a position of the mobilecomputing device 110 based on wireless signals (e.g., Wi-Fi signals orcellular signals) transmitted by the mobile computing device 110. Insome implementations, the coarse localization of the mobile computingdevice also includes an estimate of orientation of the mobile computingdevice 110. The mobile computing device 110 may be configured totransmit a request to the localization server 120 that includes thecoarse localization, and receive one or more feature point maps from thelocalization server 120 that are selected by the localization server 120based on the coarse localization. The mobile computing device 110 may beconfigured to determine a fine localization pose by localizing into afeature point map of the one or more feature point maps using capturedimages of the local surroundings 112. For example, bundle adjustmentprocessing (e.g., using a SLAM (Simultaneous Localization And Mapping)algorithm) may be applied to localize into a feature point map todetermine the fine localization pose. The fine localization pose mayinclude a second estimate of position and an estimate of orientation.

The system 100 includes a content server 130 configured to receive arequest for content that includes the fine localization pose from themobile computing device 110, and transmit content to the mobilecomputing device 110, wherein the content is selected by the contentserver 130 based on the request for content that includes the finelocalization pose. For example, the content may describe one or morevirtual objects associated with positions in the local surroundings 112.In some implementations (not shown in FIG. 1), the localization server120 and the content server 130 may be combined in a single device. Forexample, the content server 130 may be implemented on the localizationserver 500 of FIG. 5.

The mobile computing device 110 may be configured to generate a virtualobject image including a view of a virtual object based on the finelocalization pose, and display the virtual object image. In someimplementations, the mobile computing device 110 may transmit a requestfor content that includes the fine localization pose to the contentserver 130, and receive content (e.g., data describing one or morevirtual objects) associated with positions in the local surroundings 112in response to the message. For example, virtual object image (e.g., aleft-eye image and/or a right-eye image) may be presented in a displayof the mobile computing device 110. For example, the mobile computingdevice 110 may be a smartphone, a smartwatch, a tablet, or head-mounteddisplay. For example, the mobile computing device 110 may include themobile computing device 300 of FIG. 3. For example, the mobile computingdevice 110 may include the system 400 of FIG. 4.

FIG. 2 is a block diagram of an example of a system 200 configured toenable localization for CGR applications. In the system 200 the mobilecomputing device includes a head-mounted display 210. The head-mounteddisplay 210 is worn by a user 216 while the user views localsurroundings 212. The head-mounted display 210 may be configured tocommunicate with the localization server 120 and the content server 130via the communications network 106 in order to determine a finelocalization for the head-mounted display 210 and generate and displayvirtual object images based on the fine localization (e.g., a finelocalization pose in a global coordinate system). For example, thehead-mounted display 210 may implement the process 600 of FIG. 6. Forexample, the head-mounted display 210 may include the mobile computingdevice 300 of FIG. 3. For example, the head-mounted display 210 mayinclude the head-mounted display 410 of FIG. 4.

FIG. 3 is a block diagram of an example of a mobile computing device 300configured to enable localization for CGR applications. The mobilecomputing device 300 includes a processing apparatus 310, a data storagedevice 320, one or more motion sensors 330, one or more image sensors340, a display 350, and an interconnect 370 through which the processingapparatus 310 may access the other components. The mobile computingdevice 300 may be configured to determine a fine localization (e.g.,including a global position and/or a global orientation) by localizinginto a feature point map selected based on a coarse localizationdetermined based on motion sensor data. For example, the mobilecomputing device 300 may be configured to implement the process 600 ofFIG. 6. For example, the mobile computing device 300 may be configuredto implement the process 700 of FIG. 7. For example, the mobilecomputing device 300 may be configured to implement the process 800 ofFIG. 8.

The processing apparatus 310 may be operable to execute instructionsthat have been stored in a data storage device 320. In someimplementations, the processing apparatus 310 is a processor with randomaccess memory for temporarily storing instructions read from the datastorage device 320 while the instructions are being executed. Theprocessing apparatus 310 may include single or multiple processors eachhaving single or multiple processing cores. Alternatively, theprocessing apparatus 310 may include another type of device, or multipledevices, capable of manipulating or processing data. For example, thedata storage device 320 may be a non-volatile information storage devicesuch as a hard drive, a solid-state drive, a read-only memory device(ROM), an optical disc, a magnetic disc, or any other suitable type ofstorage device such as a non-transitory computer readable memory. Thedata storage device 320 may include another type of device, or multipledevices, capable of storing data for retrieval or processing by theprocessing apparatus 310. The processing apparatus 310 may access andmanipulate data stored in the data storage device 320 via theinterconnect 370. For example, the data storage device 320 may storeinstructions executable by the processing apparatus 310 that uponexecution by the processing apparatus 310 cause the processing apparatus310 to perform operations (e.g., operations that implement the process600 of FIG. 6). In some implementations, the processing apparatus 310and the data storage device 320 are attached to the display 350.

The one or more motions sensors 330 may be configured to detect motionof the mobile computing device 300. For example, the one or more motionssensors 330 may include one or more accelerometers, gyroscopes, and/ormagnetometers. For example, the one or more motions sensors 330 mayinclude a global positioning system (GPS) receiver. In someimplementations, the one or more motions sensors 330 are coupled (e.g.,attached) to the display 350 (e.g., a head-mounted display). In someimplementations, an orientation and/or a position of mobile computingdevice 300 in a real space may be determined based on motion sensor datafrom the one or more motions sensors 330. For example, changes in theorientation and/or a position of the mobile computing device 300 may beused as a control interface for a user to change a view of a CGRenvironment of a CGR application that is presented using the display350.

The one or more image sensors 340 may be configured to capture images,converting light incident on the one or more image sensors 340 into oneor more digital images. In some implementations, the one or more imagesensors 340 are coupled (e.g., attached) to the display 350 (e.g., ahead-mounted display). The one or more image sensors 340 may detectlight of a certain spectrum (e.g., a visible spectrum and/or an infraredspectrum) and convey information constituting an image as electricalsignals (e.g., analog or digital signals). For example, the one or moreimage sensors 340 may include charge-coupled devices (CCD) or activepixel sensors in complementary metal-oxide-semiconductor (CMOS). In someimplementations, the one or more image sensors 340 include ananalog-to-digital converter. For example, the one or more image sensors340 may include an infrared camera and a visible light camera. The oneor more image sensors 340 may include an image sensor configured tocapture images of a vicinity of the mobile computing device 300. In someimplementations, the one or more image sensors 340 include an array ofimage sensors arranged around a device (e.g., the head-mounted display210) to provide a collective field of view spanning a wide angle. Forexample, the one or more image sensors 340 may be arranged to provide apanoramic view (e.g., a 360 degree panoramic view) of an area around ahead-mounted display. For example, the one or more image sensors 340 mayreceive light through respective lenses (e.g., a fisheye lens or arectilinear lens).

The display 350 includes a screen, a lens, or another type of opticalassembly configured to direct light to the eyes of a user to enable thepresentation of images (e.g., video frames) to the user. For example,the display 350 may include a touchscreen display, where the mobilecomputing device 300 is smartphone or tablet. In some implementations,the display 350 includes a head-mounted display (e.g., smart glasses),which may be held in place on a face of the user by a fastening article(e.g., a headband or a frame). In some implementations, a screen of thedisplay 350 is positioned directly in front of eyes of the user. In someimplementations, the display 350 includes an optical assembly (e.g., alens and/or a mirror) that is positioned directly in front of eyes ofthe user and configured to direct light from a screen or projector ofthe display 350 to the eyes of the user. The optical assembly may alsodirect light from an environment around the user to eyes of the user.For example, the optical assembly may include a partially reflectivepolarizing film applied to an inner surface of a transparent visor. Theoptical assembly may function as an optical combiner. For example, alens of the optical assembly may also let light from an environment infront of the user pass through to reach eyes of the user and allow theuser to see in front of him while having objects of a CGR environmentdepicted in an image presented by the display 350 overlaid on a view ofthe physical environment in front of the user.

The network interface 360 facilitates communication with other devices,for example, the localization server 120 or the content server 130. Forexample, network interface 360 may facilitate communication via thecommunications network 106. For example, network interface 360 mayfacilitate communication via a Wi-Fi network, a cellular network and/ora wired network. For example, network interface 360 may facilitatecommunication via a WiMAX network. For example, network interface 360may facilitate communication via a fiber optic network.

For example, the interconnect 370 may be a system bus, or a wired orwireless network (e.g., a body area network).

The processing apparatus 310 may be configured to enable localizationfor CGR applications. For example, the processing apparatus 310 may beconfigured to access motion data captured using the one or more motionsensors 330, and determine, based on the motion data, a coarselocalization pose. For example, the coarse localization pose may includea first estimate of position of a head-mounted display of the display350 and a first estimate of orientation of the head-mounted display. Forexample, the processing apparatus 310 may be configured to obtain one ormore feature point maps. The feature point maps may be associated with aposition of the coarse localization pose. For example, the processingapparatus 310 may be configured to access images captured using the oneor more image sensors 340, and determine, based on the images, a finelocalization pose by localizing into a feature point map of the one ormore feature point maps. For example, the fine localization pose mayinclude a second estimate of position of the head-mounted display and asecond estimate of orientation of the head-mounted display. For example,the processing apparatus 310 may be configured to generate, based on thefine localization pose, a virtual object image including a view of avirtual object, and display the virtual object image using thehead-mounted display. For example, the processing apparatus 310 may beconfigured to obtain the one or more feature point maps by transmitting,via a communications network (e.g., the communications network 106), thecoarse localization pose to a localization server (e.g., thelocalization server 120), and receiving, via the communications network,the one or more feature point maps from the localization server. In someimplementations, the one or more feature point maps from thelocalization server include a plurality of feature point maps receivedin succession, and the processing apparatus 310 may be configured todetermine the fine localization pose by iteratively attempting tolocalize into the feature point maps of the plurality of feature pointmaps as they are received, requesting a next feature point map of theplurality of feature point maps from the localization server afterfailing to localize into a current feature point map of the plurality offeature point maps, and terminating reception of feature point maps ofthe plurality of feature point maps from the localization serverresponsive to successfully localizing into a current feature point mapof the plurality of feature point maps. For example, the one or morefeature point maps may be stored in an octree data structure that maps aphysical space. For example, the one or more feature point maps may beassociated with respective coordinates in a global coordinate system.

FIG. 4 is a block diagram of an example of a system 400 configured toenable localization for CGR applications. The system 400 includes ahead-mounted display 410 and a computing device 450 that communicate viawireless communications link 425. The head-mounted display 410 includesone or more motions sensors 412, one or more image sensors 414, awireless communications interface 416, a display 422, an interconnect418 through which components of the head-mounted display may exchangeinformation (e.g., under the control of microcontroller or otherprocessing apparatus in the head-mounted display 410 that is not shownin FIG. 4), and a fastening article 420 configured to hold thehead-mounted display 410 in place on a head of a user that is wearingthe head-mounted display 410. The computing device 450 includes aprocessing apparatus 460, a data storage device 470, a wirelesscommunications interface 480, a user interface 490, a network interface492, and an interconnect 494 through which the processing apparatus 460may access the other components of the computing device 450. Thecomputing device 450 may be positioned near a user wearing thehead-mounted display 410 and may perform computational tasks to controlthe head-mounted display 410. For example, the computing device 450 maybe a smartphone, a tablet, a laptop, a desktop computer, or an appliance(e.g., a smart television or a smart speaker) on a table located in aroom with the user, or the computing device 450 may be another wearabledevice worn at a different body part of the user (e.g., integrated witha vest worn on a chest). The system 400 may be configured to determine afine localization (e.g., including a global position and/or a globalorientation) by localizing into a feature point map selected based on acoarse localization determined based on motion sensor data. For example,the system 400 may be configured to implement the process 600 of FIG. 6.For example, the system 400 may be configured to implement the process700 of FIG. 7. For example, the system 400 may be configured toimplement the process 800 of FIG. 8.

The head-mounted display 410 includes one or more motion sensors 412.The one or more motions sensors 412 may be configured to detect motionof the head-mounted display 410. For example, the one or more motionssensors 412 may include one or more accelerometers, gyroscopes, and/ormagnetometers. For example, the one or more motions sensors 412 mayinclude a global positioning system (GPS) receiver. The one or moremotions sensors 412 may be coupled (e.g., attached) to the head-mounteddisplay 410. In some implementations, an orientation and/or a positionof the head-mounted display 410 in a real space may be determined basedon sensor data from the one or more motions sensors 412. For example,changes in the orientation and/or a position of the head-mounted display410 may be used as a control interface for a user to change a view of aCGR environment of a CGR application that is presented using thehead-mounted display 410.

The head-mounted display 410 includes one or more image sensors 414. Theone or more image sensors 414 may be configured to capture images,converting light incident on the one or more image sensors 414 into oneor more digital images. The one or more image sensors 414 are coupled(e.g., attached) to the head-mounted display 410. The one or more imagesensors 414 may detect light of a certain spectrum (e.g., a visiblespectrum and/or an infrared spectrum) and convey informationconstituting an image as electrical signals (e.g., analog or digitalsignals). For example, the one or more image sensors 414 may includecharge-coupled devices (CCD) or active pixel sensors in complementarymetal-oxide-semiconductor (CMOS). In some implementations, the one ormore image sensors 414 include an analog-to-digital converter. Forexample, the one or more image sensors 414 may include an infraredcamera and a visible light camera. The one or more image sensors 414 mayinclude an image sensor configured to capture images of a vicinity ofthe head-mounted display 410. In some implementations, the one or moreimage sensors 414 include an array of image sensors arranged around thehead-mounted display 410 to provide a collective field of view spanninga wide angle. For example, the one or more image sensors 414 may bearranged to provide a panoramic view (e.g., a 360 degree panoramic view)of an area around the head-mounted display 410. For example, the one ormore image sensors 414 may receive light through respective lenses(e.g., a fisheye lens or a rectilinear lens).

The head-mounted display 410 includes a wireless communicationsinterface 416. The wireless communications interface 416 facilitatescommunication with other devices, including the computing device 450.For example, wireless communications interface 416 may facilitatecommunication via a Wi-Fi network, a Bluetooth link, or a ZigBee link.In some implementations, the wireless communications interface 416 maybe used to receive, from the computing device 450, data and/orinstructions invoking presentation using the display 422 of a view of aCGR environment. In some implementations, the wireless communicationsinterface 416 may be used to transmit sensor data from the one or moremotion sensors 412 and/or images captured using the one or more imagesensors 414 to the computing device 450.

The head-mounted display 410 includes a display 422. The display 422 maybe configured to present images, converting digital images into lightprojected from the display 422. The display 422 may project light usingan array of pixels that project light in a visible spectrum. The display422 may include a screen, a lens, or another type of optical assemblyconfigured to direct light to the eyes of a user wearing thehead-mounted display 410 to enable the presentation of images (e.g.,video frames) to the user. For example, the display 422 may include ascreen, such as a liquid crystal display (LCD), a light emitting diode(LED) display (e.g., an OLED display), or other suitable screen. Forexample, the display 422 may include a projector. In someimplementations, a screen of the display 422 is positioned directly infront of eyes of the user. In some implementations, the display 422includes an optical assembly (e.g., a lens and/or a mirror) that ispositioned directly in front of eyes of the user and configured todirect light from a screen or projector of the display 422 to the eyesof the user. The optical assembly may also direct light from anenvironment around the user to eyes of the user. For example, theoptical assembly may include a partially reflective polarizing filmapplied to an inner surface of a transparent visor. The optical assemblymay function as an optical combiner. For example, a lens of the opticalassembly may also let light from a physical environment in front of theuser pass through to reach eyes of the user and allow the user to see infront of him while having objects of a CGR environment depicted in animage presented by the display 422 overlaid on a view of the physicalenvironment in front of the user. In some implementations, atransparency of the optical assembly (e.g., a lens) may be adjusted tosuit a computer generated reality application (e.g., a virtual realityapplication or an augmented reality application).

For example, the interconnect 418 may be a system bus, or a wired orwireless network (e.g., a body area network).

The head-mounted display 410 includes a fastening article 420. Thefastening article 420 may be configured to hold the head-mounted display410 in place on a head of a user when the user is wearing thehead-mounted display 410. For example, the fastening article 420 mayinclude a headband. For example, the fastening article 420 may include aframe with arms that rest on ears of the user and hold a lens or ascreen of the display 422 in front of an eye of the user.

The computing device 450 includes a processing apparatus 460. Theprocessing apparatus 460 may be operable to execute instructions thathave been stored in a data storage device 470. In some implementations,the processing apparatus 460 is a processor with random access memoryfor temporarily storing instructions read from the data storage device470 while the instructions are being executed. The processing apparatus460 may include single or multiple processors each having single ormultiple processing cores. Alternatively, the processing apparatus 460may include another type of device, or multiple devices, capable ofmanipulating or processing data. For example, the data storage device470 may be a non-volatile information storage device such as a harddrive, a solid-state drive, a read-only memory device (ROM), an opticaldisc, a magnetic disc, or any other suitable type of storage device suchas a non-transitory computer readable memory. The data storage device470 may include another type of device, or multiple devices, capable ofstoring data for retrieval or processing by the processing apparatus460. The processing apparatus 460 may access and manipulate data storedin the data storage device 470 via interconnect 494. For example, thedata storage device 470 may store instructions executable by theprocessing apparatus 460 that upon execution by the processing apparatus460 cause the processing apparatus 460 to perform operations (e.g.,operations that implement the process 600 of FIG. 6).

The computing device 450 includes a wireless communications interface480. The wireless communications interface 480 facilitates communicationwith other devices, including the head-mounted display 410. For example,wireless communications interface 480 may facilitate communication via aWi-Fi network, a Bluetooth link, or a ZigBee link. The wirelesscommunications interface 480 may be used to establish the wirelesscommunications link 425 with the head-mounted display 410. In someimplementations, the wireless communications interface 480 may be usedto receive sensor data (e.g., motion sensor data and/or images) from thehead-mounted display 410. In some implementations, the wirelesscommunications interface 480 may be used to transmit, to thehead-mounted display 410, data and/or instructions invoking presentationusing the display 422 of a view of a CGR environment.

The computing device 450 includes a user interface 490. For example, theuser interface 490 may include a touchscreen display. For example, theuser interface 490 may include a microphone configured receive speechcommands. For example, the user interface 490 may include an imagesensor configured to detect hand gesture commands. For example, the userinterface 490 may include a keyboard, a mouse, a joystick, and/oranother handheld controller. For example, the user interface 490 mayenable a user (e.g., the user wearing the head-mounted display 410) toenter commands to a CGR running on the computing device 450 and/or tochange the configuration of a process associated with an object of a CGRenvironment of the CGR application.

The computing device 450 includes a network interface 492. The networkinterface 492 facilitates communication with other devices, for example,the localization server 120 or the content server 130. For example,network interface 492 may facilitate communication via thecommunications network 106. For example, network interface 492 mayfacilitate communication via a Wi-Fi network, a cellular network and/ora wired network. For example, network interface 492 may facilitatecommunication via a WiMAX network. For example, network interface 492may facilitate communication via a fiber optic network.

For example, the interconnect 494 may be a system bus, or a wired orwireless network (e.g., a body area network).

The processing apparatus 460 may be configured to enable localizationfor CGR applications. For example, the processing apparatus 460 may beconfigured to access motion data captured using the one or more motionsensors 412, and determine, based on the motion data, a coarselocalization pose. For example, the coarse localization pose may includea first estimate of position of the head-mounted display 410 and a firstestimate of orientation of the head-mounted display. For example, theprocessing apparatus 460 may be configured to obtain one or more featurepoint maps. The feature point maps may be associated with a position ofthe coarse localization pose. For example, the processing apparatus 460may be configured to access images captured using the one or more imagesensors 414, and determine, based on the images, a fine localizationpose by localizing into a feature point map of the one or more featurepoint maps. For example, the fine localization pose may include a secondestimate of position of the head-mounted display and a second estimateof orientation of the head-mounted display. For example, the processingapparatus 460 may be configured to generate, based on the finelocalization pose, a virtual object image including a view of a virtualobject, and display the virtual object image using the head-mounteddisplay. For example, the processing apparatus 460 may be configured toobtain the one or more feature point maps by transmitting, via acommunications network (e.g., the communications network 106), thecoarse localization pose to a localization server (e.g., thelocalization server 120), and receiving, via the communications network,the one or more feature point maps from the localization server. In someimplementations, the one or more feature point maps from thelocalization server include a plurality of feature point maps receivedin succession, and the processing apparatus 460 may be configured todetermine the fine localization pose by iteratively attempting tolocalize into the feature point maps of the plurality of feature pointmaps as they are received, requesting a next feature point map of theplurality of feature point maps from the localization server afterfailing to localize into a current feature point map of the plurality offeature point maps, and terminating reception of feature point maps ofthe plurality of feature point maps from the localization serverresponsive to successfully localizing into a current feature point mapof the plurality of feature point maps. For example, the one or morefeature point maps may be stored in an octree data structure that maps aphysical space. For example, the one or more feature point maps may beassociated with respective coordinates in a global coordinate system.

In some implementations, (not shown in FIG. 4), processing for a CGRapplication may be distributed between a processing apparatus in thehead-mounted display 410 and the processing apparatus 460. For example,a simulation process may be run on a processing apparatus of thehead-mounted display 410 to reduce latency for updates to the view ofthe CGR environment, while one or more processes associated with objectsin the CGR environment may be run on the processing apparatus 460 toupdate the states of the objects. In some implementations, realityfragments may be transmitted via the wireless communications link 425between the head-mounted display 410 and the computing device 450. Thus,the processing apparatus of the head-mounted display 410 and theprocessing apparatus 460 may operate as single processing apparatusdistributed between the head-mounted display 410 and the computingdevice 450 that runs the CGR application and implements processesdescribed herein (e.g., the process 600 of FIG. 6).

FIG. 5 is a block diagram of an example of a localization server 500configured to enable localization for CGR applications. The localizationserver 500 includes a processing apparatus 510, a data storage device520, a network interface 530, a user interface 540, and an interconnect570 through which the processing apparatus 510 may access the othercomponents. The localization server 500 may be configured to identifyone or more feature point maps selected based on a coarse localization(e.g., including a global position and/or a global orientation), whichmay have been determined based on motion sensor data for a mobilecomputing device. For example, the localization server 500 may beconfigured to implement the process 900 of FIG. 9.

The processing apparatus 510 may be operable to execute instructionsthat have been stored in a data storage device 520. In someimplementations, the processing apparatus 510 is a processor with randomaccess memory for temporarily storing instructions read from the datastorage device 520 while the instructions are being executed. Theprocessing apparatus 510 may include single or multiple processors eachhaving single or multiple processing cores. Alternatively, theprocessing apparatus 510 may include another type of device, or multipledevices, capable of manipulating or processing data. For example, thedata storage device 520 may be a non-volatile information storage devicesuch as a hard drive, a solid-state drive, a read-only memory device(ROM), an optical disc, a magnetic disc, or any other suitable type ofstorage device such as a non-transitory computer readable memory. Thedata storage device 520 may include another type of device, or multipledevices, capable of storing data for retrieval or processing by theprocessing apparatus 510. The processing apparatus 510 may access andmanipulate data stored in the data storage device 520 via theinterconnect 570. For example, the data storage device 520 may storeinstructions executable by the processing apparatus 510 that uponexecution by the processing apparatus 510 cause the processing apparatus510 to perform operations (e.g., operations that implement the process900 of FIG. 9).

The network interface 530 facilitates communication with other devices,for example, the mobile computing device 110 or the head-mounted display210. For example, network interface 530 may facilitate communication viathe communications network 106. For example, network interface 530 mayfacilitate communication via a Wi-Fi network, a cellular network and/ora wired network. For example, network interface 530 may facilitatecommunication via a WiMAX network. For example, network interface 530may facilitate communication via a fiber optic network.

The localization server 500 includes a user interface 540. For example,the user interface 540 may include a touchscreen display. For example,the user interface 540 may include a keyboard, a mouse, a joystick,and/or another handheld controller. For example, the user interface 540may include a microphone configured receive speech commands. Forexample, the user interface 540 may include an image sensor configuredto detect hand gesture commands. For example, the user interface 540 mayenable a user (e.g., a system administrator) to enter commands tolocalization server to configure and/or maintain a collection featurepoint maps stored in a spatially partitioned data structure and/or otheraspects of a localization service. For example, a feature point map maybe updated based on new scans of regions space that apply a featureextraction algorithm to images of the region of space. In someimplementations, global pose information associated with scanned imagesmay be manually determined and entered based on surveying data and/ordetailed design blueprints for buildings or other structures.

FIG. 6 is a flowchart of an example of a process 600 for localizationfor CGR applications. The process 600 includes accessing 610 motion datacaptured using one or more motion sensors; determining 620, based on themotion data, a coarse localization, wherein the coarse localizationincludes an first estimate of position; obtaining 640 one or morefeature point maps associated with a position of the coarselocalization; accessing 650 images captured using one or more imagesensors; determining 660, based on the images, a fine localization poseby localizing into a feature point map of the one or more feature pointmaps; generating 670, based on the fine localization pose, a virtualobject image including a view of a virtual object; and displaying 680the virtual object image. For example, the process 600 may beimplemented by the mobile computing device 110 of FIG. 1. For example,the process 600 may be implemented by the head-mounted display 210 ofFIG. 2. For example, the process 600 may be implemented by the mobilecomputing device 300 of FIG. 3. For example, the process 600 may beimplemented by the system 400 of FIG. 4.

The process 600 includes, at an electronic device having one or moremotion sensors, accessing 610 motion data captured using the one or moremotion sensors (e.g., the one or more motion sensors 330 or the one ormore motion sensors 412). For example, the one or more motions sensorsmay include one or more accelerometers, gyroscopes, and/ormagnetometers. In some implementations, the one or more motions sensorsare coupled (e.g., attached) to a display (e.g., the display 350 or thehead-mounted display 410). For example, the one or more motions sensorsmay include an inertial measurement unit. In some implementations, theone or more motion sensors include global position system receiver. Insome implementations, the one or more motion sensors include receiversconfigured to estimate a location of a device including the one or moreimage sensors based on triangulation of wireless signals from thedevice. For example, a position of the device may be determined based ontriangulation of Wi-Fi signals or cellular signals from the device. Themotion data may be accessed 610 in variety of ways. For example, themotion data may be accessed 610 by reading directly from a sensor orfrom a memory via an interconnect (e.g., the interconnect 370). Forexample, the sensor data may be accessed 610 by receiving sensor datavia a communications link (e.g., the wireless communications link 425).

The process 600 includes determining 620, based on the motion data, acoarse localization, wherein the coarse localization includes a firstestimate of position of the electronic device (e.g., position of amobile computing device). In some implementations, the coarselocalization includes a global pose. For example, a coarse localizationpose may be determined 620 based on the motion data. For example, thecoarse localization pose may include a first estimate of position of ahead-mounted display and a first estimate of orientation of thehead-mounted display. For example, a position of the coarse localizationmay be determined as latitude, longitude, and altitude values from a GPSreceiver. For example, a position of the coarse localization may bedetermined based on integration of accelerometer and/or gyroscopereadings. For example, a position of the coarse localization may bedetermined triangulating wireless signals (e.g., Wi-Fi signals orcellular signals) received from the mobile computing device by remotewireless sensors. For example, an orientation of a course localizationmay be determined based on magnetometer and accelerometer readings. Forexample, an orientation of a course localization may be determined basedon integration of gyroscope readings.

The process 600 includes obtaining 640 one or more feature point maps.The one or more feature point maps may be associated with a position ofthe coarse localization. For example, the one or more feature point mapsare associated with a position of a coarse localization pose. Forexample, the one or more feature point maps may have been stored in aspatially partitioned data structure that is searched based on thecoarse localization (e.g., a coarse localization pose). In someimplementations, the one or more feature point maps may be obtained 640from a localization server (e.g., the localization server 120). Forexample, the process 700 of FIG. 7 may be implemented to obtain 640 theone or more feature point maps. In some implementations, thelocalization server is configured to search a spatially partitioned datastructure for candidate feature point maps that are near a positioncorresponding to the coarse localization, and prioritize the candidatefeature point maps for transmission to the mobile computing device basedon distance from the position corresponding to the coarse localization,comparison of an orientation corresponding to the coarse localization toa direction of a candidate feature point map from the positioncorresponding to the coarse localization, and/or point densities offeature point maps. For example, a localization server that the one ormore feature point maps are obtained 640 from may implement the process900 of FIG. 9. In some implementations, the one or more feature pointmaps may be obtained 640 by searching a world map database. For example,the one or more feature point maps may be obtained 640 by reading theone or more feature point maps from a memory (e.g., from the datastorage device 320 or from the data storage device 470), where the worldmap database is stored locally in the mobile computing device. Forexample, the one or more feature point maps may be stored in an octreedata structure that maps a physical space. For example, the one or morefeature point maps may be associated with respective coordinates in aglobal coordinate system.

The process 600 includes accessing 650 images captured using one or moreimage sensors (e.g., the one or more image sensors 340 or the one ormore image sensors 414). In some implementations, the one or more imagesensors are coupled (e.g., attached) to the one or more motion sensors,which may include an inertial measurement unit. The one or more imagesmay depict a region of space in the vicinity of a user wearing ahead-mounted display (e.g., the head-mounted display 410). For example,an image may be accessed 610 by reading directly from an image sensor,by reading the image from memory or another storage device, or byreceiving the image via a communications link (e.g., the wirelesscommunications link 425) with another device.

The process 600 includes determining 660, based on the images, a finelocalization pose by localizing into a feature point map of the one ormore feature point maps. The fine localization pose may include a secondestimate of position and an estimate of orientation. For example, thefine localization pose may include a second estimate of position of ahead-mounted display (e.g., the head-mounted display 210 or thehead-mounted display 410) and a second estimate of orientation of thehead-mounted display. For example, bundle adjustment processing (e.g.,using a SLAM (Simultaneous Localization And Mapping) algorithm) may beapplied to localize into a feature point map to determine 660 the finelocalization pose. In some implementations, the one or more featurepoint maps from the localization server include a plurality of featurepoint maps received in succession, and determining the fine localizationpose includes iteratively attempting to localize into the feature pointmaps of the plurality of feature point maps as they are received. Forexample, the process 800 of FIG. 8 may be implemented to iterativelyattempt to localize into a sequence of feature point maps until alocalization into a feature point map is achieved.

The process 600 includes generating 670, based on the fine localizationpose, a virtual object image including a view of a virtual object. Forexample, generating 670 a virtual object image may include rendering animage depicting a virtual object at a position (e.g., a global position)associated with the virtual object, as seen from the fine localizationpose of the mobile computing device.

The process 600 includes displaying 680 the virtual object image (e.g.,a left-eye image and/or a right-eye image). For example, the virtualobject image (e.g., a left-eye image and/or a right-eye image) may bedisplayed 680 using a head-mounted display (e.g., the head-mounteddisplay 210 or the head-mounted display 410) attached to the one or moreimage sensors. For example, the virtual object image may be displayed680 using the display 350.

FIG. 7 is a flowchart of an example of a process 700 for obtainingfeature point maps associated with a coarse localization. The process700 includes transmitting 710 a coarse localization to a localizationserver; and receiving 720 one or more feature point maps from thelocalization server. For example, the process 700 may be implemented bythe mobile computing device 110 of FIG. 1. For example, the process 700may be implemented by the head-mounted display 210 of FIG. 2. Forexample, the process 700 may be implemented by the mobile computingdevice 300 of FIG. 3. For example, the process 700 may be implemented bythe system 400 of FIG. 4.

The process 700 includes transmitting 710, via a communications network(e.g., the communication network 106), the coarse localization (e.g.,including a coarse localization pose) to a localization server (e.g.,the localization server 120). For example, the coarse localization maybe transmitted 710 using the network interface 360. For example, thecoarse localization may be transmitted 710 using the network interface492.

The process 700 includes receiving 720, via the communications network(e.g., the communication network 106), one or more feature point mapsfrom the localization server (e.g., the localization server 120). Forexample, the one or more feature point maps may be received 720 usingthe network interface 360. For example, the one or more feature pointmaps may be received 720 using the network interface 492.

FIG. 8 is a flowchart of an example of a process 800 for iterativelyobtaining feature point maps associated with a coarse localization todetermine a fine localization. For example, the one or more featurepoint maps from the localization server include a sequence of featurepoint maps received in succession. For example, the localization servermay prioritize the feature point maps (e.g., using the process 900 ofFIG. 9) and arrange them in the sequence in an effort to reduce thenumber of localization attempts that will be made by the mobilecomputing device before a successful localization and to reduce thedelay associated with performing those localization attempts. Theprocess 800 includes receiving 810 a feature point map in a sequence offeature point maps; iteratively attempting to localize 820 into acurrent feature point map in the sequence of the feature point maps; if(at 825) the localization of the current feature point map is notsuccessful, requesting 830 a next feature point map of the sequence offeature point maps from the localization server; and, if (at 825) thelocalization of the current feature point map is successful, terminating840 reception of feature point maps of the sequence of feature pointmaps from the localization server. For example, the process 800 may beimplemented by the mobile computing device 110 of FIG. 1. For example,the process 800 may be implemented by the head-mounted display 210 ofFIG. 2. For example, the process 800 may be implemented by the mobilecomputing device 300 of FIG. 3. For example, the process 800 may beimplemented by the system 400 of FIG. 4.

The process 800 includes receiving 810 a feature point map in a sequenceof feature point maps. For example, the current feature point map may bereceived 810 using the network interface 360 or the network interface492.

The process 800 includes iteratively attempting to localize 820 into thefeature point maps of the sequence of feature point maps as they arereceived 810. For example, bundle adjustment processing (e.g., using aSLAM (Simultaneous Localization And Mapping) algorithm) may be appliedto attempt to localize 820 into a current feature point map to determinea fine localization pose.

When (at 825) localization into the current feature point map is notsuccessful, the process 800 includes requesting 830 a next feature pointmap of the sequence of feature point maps from the localization server(e.g., the localization server 120) after failing to localize into acurrent feature point map of the sequence of feature point maps. Forexample, requesting 830 a next feature point map may includetransmitting a request message to the localization server using thenetwork interface 360 or the network interface 492.

When (at 825) localization into the current feature point map issuccessful, the process 800 includes terminating 840 reception offeature point maps of the sequence of feature point maps from thelocalization server (e.g., the localization server 120) responsive tosuccessfully localizing into a current feature point map of the sequenceof feature point maps.

FIG. 9 is a flowchart of an example of a process 900 for identifying oneor more feature point maps for transmission based on a coarselocalization. For example, the one or more feature point maps may bestored in a spatially partitioned data structure. For example, the oneor more feature point maps may be stored in an octree data structurethat maps a physical space. In some implementations, the one or morefeature point maps are associated with respective coordinates in aglobal coordinate system. The process 900 includes searching 910 aspatially partitioned data structure for candidate feature point mapsthat are near a position corresponding to a coarse localization; andprioritizing 920 the candidate feature point maps for transmission. Forexample, the process 900 may be implemented by the localization server120 of FIG. 1. For example, the process 900 may be implemented by thelocalization server 500 of FIG. 5.

The process 900 includes searching 910 the spatially partitioned datastructure for candidate feature point maps that are near a positioncorresponding to the coarse localization (e.g., a coarse localizationpose). In some implementations, the spatially partitioned data structuremay be searched 910 to find feature point maps corresponding topositions within a maximum distance from a position of the finelocalization of the mobile computing device. In some implementations,the spatially partitioned data structure may be searched 910 to findfeature point maps corresponding to positions along a ray cast from aposition of the fine localization of the mobile computing device basedon an orientation of the fine localization of the mobile computingdevice. In some implementations, the spatially partitioned datastructure may be searched 910 to find feature point maps correspondingto positions appearing within a field of view of one or more imagesensors of the mobile computing device based on a fine localization poseof the mobile computing device.

The process 900 includes prioritizing 920 the candidate feature pointmaps for transmission. For example, the candidate feature point maps maybe prioritized 920 for transmission based on distance from the positioncorresponding to the coarse localization pose. For example, thecandidate feature point maps may be prioritized 920 for transmissionbased on comparison of an orientation corresponding to a coarselocalization pose to a direction of a candidate feature point map fromthe position corresponding to the coarse localization pose. For example,the candidate feature point maps may be prioritized 920 for transmissionbased on a feature point density of a candidate feature point map. Insome implementations, the candidate feature point maps may beprioritized 920 for transmission based on a combination of factors,including distance from a position, direction from a position, and/orpoint densities of the candidate feature point maps.

As described above, one aspect of the present technology is thegathering and use of data available from various sources to improve thedelivery to users of invitational content or any other content that maybe of interest to them. The present disclosure contemplates that in someinstances, this gathered data may include personal information data thatuniquely identifies or can be used to contact or locate a specificperson. Such personal information data can include demographic data,location-based data, telephone numbers, email addresses, twitter ID's,home addresses, data or records relating to a user's health or level offitness (e.g., vital signs measurements, medication information,exercise information), date of birth, or any other identifying orpersonal information.

The present disclosure recognizes that the use of such personalinformation data, in the present technology, can be used to the benefitof users. For example, the personal information data can be used todeliver targeted content that is of greater interest to the user.Accordingly, use of such personal information data enables users tocalculated control of the delivered content. Further, other uses forpersonal information data that benefit the user are also contemplated bythe present disclosure. For instance, health and fitness data may beused to provide insights into a user's general wellness, or may be usedas positive feedback to individuals using technology to pursue wellnessgoals.

The present disclosure contemplates that the entities responsible forthe collection, analysis, disclosure, transfer, storage, or other use ofsuch personal information data will comply with well-established privacypolicies and/or privacy practices. In particular, such entities shouldimplement and consistently use privacy policies and practices that aregenerally recognized as meeting or exceeding industry or governmentalrequirements for maintaining personal information data private andsecure. Such policies should be easily accessible by users, and shouldbe updated as the collection and/or use of data changes. Personalinformation from users should be collected for legitimate and reasonableuses of the entity and not shared or sold outside of those legitimateuses. Further, such collection/sharing should occur after receiving theinformed consent of the users. Additionally, such entities shouldconsider taking any needed steps for safeguarding and securing access tosuch personal information data and ensuring that others with access tothe personal information data adhere to their privacy policies andprocedures. Further, such entities can subject themselves to evaluationby third parties to certify their adherence to widely accepted privacypolicies and practices. In addition, policies and practices should beadapted for the particular types of personal information data beingcollected and/or accessed and adapted to applicable laws and standards,including jurisdiction-specific considerations. For instance, in the US,collection of or access to certain health data may be governed byfederal and/or state laws, such as the Health Insurance Portability andAccountability Act (HIPAA); whereas health data in other countries maybe subject to other regulations and policies and should be handledaccordingly. Hence different privacy practices should be maintained fordifferent personal data types in each country.

Despite the foregoing, the present disclosure also contemplatesembodiments in which users selectively block the use of, or access to,personal information data. That is, the present disclosure contemplatesthat hardware and/or software elements can be provided to prevent orblock access to such personal information data. For example, in the caseof advertisement delivery services, the present technology can beconfigured to allow users to select to “opt in” or “opt out” ofparticipation in the collection of personal information data duringregistration for services or anytime thereafter. In another example,users can select not to provide location data for targeted contentdelivery services. In yet another example, users can select to limit thelength of time location data is maintained or entirely prohibit thedevelopment of a location history. In addition to providing “opt in” and“opt out” options, the present disclosure contemplates providingnotifications relating to the access or use of personal information. Forinstance, a user may be notified upon downloading an app that theirpersonal information data will be accessed and then reminded again justbefore personal information data is accessed by the app.

Moreover, it is the intent of the present disclosure that personalinformation data should be managed and handled in a way to minimizerisks of unintentional or unauthorized access or use. Risk can beminimized by limiting the collection of data and deleting data once itis no longer needed. In addition, and when applicable, including incertain health related applications, data de-identification can be usedto protect a user's privacy. De-identification may be facilitated, whenappropriate, by removing specific identifiers (e.g., date of birth,etc.), controlling the amount or specificity of data stored (e.g.,collecting location data a city level rather than at an address level),controlling how data is stored (e.g., aggregating data across users),and/or other methods.

Therefore, although the present disclosure broadly covers use ofpersonal information data to implement one or more various disclosedembodiments, the present disclosure also contemplates that the variousembodiments can also be implemented without the need for accessing suchpersonal information data. That is, the various embodiments of thepresent technology are not rendered inoperable due to the lack of all ora portion of such personal information data. For example, content can beselected and delivered to users by inferring preferences based onnon-personal information data or a bare minimum amount of personalinformation, such as the content being requested by the deviceassociated with a user, other non-personal information available to thecontent delivery services, or publicly available information.

Implementations or portions of implementations of the above disclosurecan take the form of a computer program product accessible from, forexample, a computer-usable or computer-readable medium. Acomputer-usable or computer-readable medium can be any device that can,for example, tangibly contain, store, communicate, or transport aprogram or data structure for use by or in connection with anyprocessor. The medium can be, for example, an electronic, magnetic,optical, electromagnetic, or semiconductor device. Other suitablemediums are also available. Such computer-usable or computer-readablemedia can be referred to as non-transitory memory or media, and caninclude RAM or other volatile memory or storage devices that can changeover time.

What is claimed is:
 1. A system comprising: a display device; one ormore image sensors; one or more motion sensors; and a processingapparatus configured to: determine, based on motion data captured usingthe one or more motion sensors, a coarse localization pose, wherein thecoarse localization pose includes a first estimate of position of thedisplay device and a first estimate of orientation of the displaydevice; obtain one or more feature point maps by transmitting the coarselocalization pose to a server and receiving the one or more featurepoint maps from the server, wherein the one or more feature point mapsare associated with a position corresponding to the coarse localizationpose and the one or more feature point maps from the server include aplurality of feature point maps received in succession that have beenprioritized by the server based on distance from the positioncorresponding to the coarse localization pose; determine, based onimages captured using the one or more image sensors, a fine localizationpose by localizing into a feature point map of the one or more featurepoint maps, wherein the fine localization pose includes a secondestimate of position of the display device and a second estimate oforientation of the display device; generate, based on the finelocalization pose, a virtual object image including a view of a virtualobject; and display the virtual object image using the display device.2. The system of claim 1, wherein the coarse localization pose istransmitted, via a communications network, to the server and the one ormore feature point maps are received, via the communications network,from the server.
 3. The system of claim 1, wherein the processingapparatus is configured to determine the fine localization pose by:iteratively attempting to localize into the feature point maps of theplurality of feature point maps as they are received; requesting a nextfeature point map of the plurality of feature point maps from the serverafter failing to localize into a current feature point map of theplurality of feature point maps; and terminating reception of featurepoint maps of the plurality of feature point maps from the serverresponsive to successfully localizing into a current feature point mapof the plurality of feature point maps.
 4. The system of claim 1,wherein the one or more feature point maps are stored in a spatiallypartitioned data structure, and the server is configured to: search thespatially partitioned data structure for candidate feature point mapsthat are near the position corresponding to the coarse localizationpose.
 5. The system of claim 4, wherein the server is configured to:prioritize the candidate feature point maps for transmission based oncomparison of an orientation corresponding to the coarse localizationpose to a direction of a candidate feature point map from the positioncorresponding to the coarse localization pose.
 6. The system of claim 4,wherein the server is configured to: prioritize the candidate featurepoint maps for transmission based on a feature point density of acandidate feature point map.
 7. The system of claim 1, wherein the oneor more feature point maps are stored in an octree data structure thatmaps a physical space.
 8. The system of claim 1, wherein the one or morefeature point maps are associated with respective coordinates in aglobal coordinate system.
 9. The system of claim 1, wherein the one ormore motion sensors include global position system receiver.
 10. Amethod comprising: determining, based on motion data captured using oneor more motion sensors, a coarse localization, wherein the coarselocalization includes a first estimate of position of an electronicdevice including the one or more motion sensors; obtaining one or morefeature point maps by transmitting the coarse localization to a serverand receiving the one or more feature point maps from the server,wherein the one or more feature point maps are associated with aposition corresponding to the coarse localization and the one or morefeature point maps from the server include a plurality of feature pointmaps received in succession that have been prioritized by the serverbased on distance from the position corresponding to the coarselocalization; determining, based on images captured using one or moreimage sensors of the electronic device, a fine localization pose bylocalizing into a feature point map of the one or more feature pointmaps, wherein the fine localization pose includes a second estimate ofposition and an estimate of orientation; generating, based on the finelocalization pose, a virtual object image including a view of a virtualobject; and displaying the virtual object image.
 11. The method of claim10, wherein the one or more motion sensors include receivers configuredto estimate a location of the electronic device based on triangulationof wireless signals from the electronic device.
 12. The method of claim10, wherein the coarse localization includes a global pose.
 13. Themethod of claim 10, wherein the virtual object image is displayed usinga head-mounted display attached to the one or more image sensors. 14.The method of claim 10, wherein the coarse localization is transmitted,via a communications network, to the server and the one or more featurepoint maps are received, via the communications network, from theserver.
 15. The method of claim 10, wherein determining the finelocalization pose comprises: iteratively attempting to localize into thefeature point maps of the plurality of feature point maps as they arereceived; requesting a next feature point map of the plurality offeature point maps from the server after failing to localize into acurrent feature point map of the plurality of feature point maps; andterminating reception of feature point maps of the plurality of featurepoint maps from the server responsive to successfully localizing into acurrent feature point map of the plurality of feature point maps. 16.The method of claim 10, wherein the one or more feature point maps arestored in a spatially partitioned data structure, and the server isconfigured to: search the spatially partitioned data structure forcandidate feature point maps that are near the position corresponding tothe coarse localization.
 17. The method of claim 16, wherein the serveris configured to: prioritize the candidate feature point maps fortransmission based on comparison of an orientation corresponding to thecoarse localization to a direction of a candidate feature point map fromthe position corresponding to the coarse localization.
 18. The method ofclaim 16, wherein the server is configured to: prioritize the candidatefeature point maps for transmission based on a feature point density ofa candidate feature point map.
 19. The method of claim 10, wherein theone or more feature point maps are stored in an octree data structurethat maps a physical space.
 20. A non-transitory computer-readablestorage medium comprising executable instructions that, when executed bya processor, facilitate performance of operations comprising:determining, based on motion data captured using one or more motionsensors, a coarse localization, wherein the coarse localization includesa first estimate of position; obtaining one or more feature point mapsby transmitting the coarse localization to a server and receiving theone or more feature point maps from the server, wherein the one or morefeature point maps are associated with a position corresponding to thecoarse localization and the one or more feature point maps from theserver include a plurality of feature point maps received in successionthat have been prioritized by the server based on distance from theposition corresponding to the coarse localization; determining, based onimages captured using one or more image sensors, a fine localizationpose by localizing into a feature point map of the one or more featurepoint maps, wherein the fine localization pose includes a secondestimate of position and an estimate of orientation; generating, basedon the fine localization pose, a virtual object image including a viewof a virtual object; and displaying the virtual object image.